Mikheil Saakashvili, Georgia's former president, who turned to opposition politics in Ukraine, has been making international headlines over the past months with a string of dramatic scenes of unrest.

Last September, he used a crowd of supporters to barge past guards to enter Ukraine from the Polish border, to protest against the Ukrainian government's decision to strip him of his Ukrainian citizenship.

In December, Saakashvili climbed on the roof of a building in the Ukrainian capital, Kiev, as armed police stormed his apartment. After he was dragged down by the security forces and bundled into a police van, a group of supporters rushed to his aid, ripping off the doors of the vehicle to allow his escape.

The latest dramatic episode came on Monday, when a large group of men in military uniforms dragged him out of a restaurant and deported him to Poland. Saakashvili called the move "kidnapping".

What's behind the ordeal?

Saakashvili was granted Ukrainian citizenship in 2015 by President Petro Poroshenko, who made him governor of Ukraine's Odessa region.

Poroshenko said Saakashvili would help Ukraine battle corruption, citing his success of all but eradicating it in Georgia during his presidency there from 2004 to 2013.

But a year later, Saakashvili resigned and called for Poroshenko's removal, accusing the Ukrainian president of protecting corrupt Ukrainians.

The president reacted by stripping his former ally of his citizenship in July 2017, turning him into a stateless person, since Saakashvili lost his Georgian citizenship to accept the Ukrainian one.

The development gave him more notoriety, boosting his voice against the Ukrainian leader.

Why Poland?

The Ukrainian government had three choices in dealing with Saakashvili: an arrest, deportation to Georgia, or exile in Poland.

Ukrainian prosecutors accuse Saakashvili of having assisted a criminal organisation - a charge that is widely seen as trumped up.

Security services said he received financing from a "criminal group" linked to former Ukrainian President Viktor Yanukovich during the 2014 Ukrainian revolution.

The Ukrainian government refrained from arresting Saakashvili to avoid turning the former Georgian politician into a cause celebre, and to avoid international condemnation for holding a political prisoner.

The second option would have had a similar effect, since Saakashvili faces prison in Georgia for what he calls politically-motivated charges over abuse of presidential office with his pardon powers.

Saakashvili believes that the Georgian government asked Ukraine not to extradite him to Tbilisi, the Georgian capital. "The Georgian government is afraid of me," he told Ukraine's News One broadcaster.

Exile in Poland would hardly stop Saakashvili from campaigning against Poroshenko, but it seems to have been considered the least damaging for Ukraine's image.

He crossed the border into Ukraine without a passport from Poland, so it seemed logical to return him to the country.

What next?

Shortly after his deportation on Monday, Saakashvili told his supporters through a phone comment to News One that he would "fight to the end" against Poroshenko's government.

"I am with you and I will fight to the end. To their end and to our victory," he said. He also said that he was not claiming asylum in Poland.

On Tuesday, Saakashvili appealed for help to the European Union and German Chancellor Angela Merkel. In an interview with German publication Bild, he described the deportation as kidnapping.

"If the European Union and especially Chancellor Angela Merkel don't finally do something ... Ukraine will break apart," he said, directly accusing Poroshenko of ordering the operation against him.

Carl Bildt, a former Swedish prime minister, said on Twitter: "Depriving Saakashvili of his only citizenship was a clear violation of his human rights. Forcibly deporting him makes things even worse."

Serhiy Leshchenko, a Ukrainian journalist and Member of Parliament, said the move was "the worst example of selective justice", adding that Poroshenko "shot himself in the foot".

Georgia's Defence Minister Levan Izoria supported Ukraine's move, saying: "When there are facts indicating breach of law, one must face justice [even if he is a former president]."